Patent Literature 1 discloses a polarizing film containing a compound (dichroic pigment) which is dispersed in an aligned polymerizable liquid crystal compound and which absorbs dichroic light. Patent Literature 1 does not, however, disclose a polarizing film which contains a dichroic pigment having a maximum absorption wavelength in a range of 350 nm to 510 nm and which is thus high in dichroic ratio.
Patent Literature 2 discloses, as a dichroic pigment having a maximum absorption wavelength in a range of 350 nm to 550 nm, a bisazo pigment having a 1,4-naphthyl structure. However, a polarizing film containing the bisazo pigment is low in dichroic ratio.
Patent Literature 3 discloses a polarizing film which has a high dichroic ratio. However, a dichroic pigment contained in the polarizing film has a maximum absorption wavelength of 518 nm or higher.